Moved check_structure detection from center of kart to the front

of the kart (which will work better for a photo finish). Hopefully
no other side effect.

src/karts/abstract_kart.hpp

@@ -157,6 +157,10 @@ public:
     /** Returns true if this kart has no wheels. */
     bool isWheeless() const;
     // ------------------------------------------------------------------------
+    /** Returns the coordinates of the front of the kart. This is used for
+     *  determining when the lap line is crossed. */
+    virtual const Vec3& getFrontXYZ() const = 0;
+    // ------------------------------------------------------------------------
     /** Returns the position of a wheel relative to the kart.
      *  \param i Index of the wheel: 0=front right, 1 = front left, 2 = rear
      *           right, 3 = rear left.  */

src/karts/kart.cpp

@@ -408,6 +408,8 @@ void Kart::reset()
         m_skidmarks->adjustFog(track->isFogEnabled() );
     }
 
+    Vec3 front(0, 0, getKartLength()*0.5f);
+    m_xyz_front = getTrans()(front);
 
     m_terrain_info->update(getTrans());
 
@@ -1190,6 +1192,9 @@ void Kart::update(float dt)
         m_body->getBroadphaseHandle()->m_collisionFilterGroup = 0;
     }
 
+    Vec3 front(0, 0, getKartLength()*0.5f);
+    m_xyz_front = getTrans()(front);
+
     m_terrain_info->update(getTrans(), epsilon);
     if(m_body->getBroadphaseHandle())
     {

src/karts/kart.hpp

@@ -102,6 +102,10 @@ private:
     /** Current race position (1-num_karts). */
     int m_race_position;
 
+    /** The coordinates of the front of the kart, used to determine when a
+     *  new lap is triggered. */
+    Vec3 m_xyz_front;
+
     /** True if the kart is eliminated. */
     bool m_eliminated;
 
@@ -292,6 +296,10 @@ public:
     /** Returns the current position of this kart in the race. */
     virtual int    getPosition         () const { return m_race_position;    }
     // ------------------------------------------------------------------------
+    /** Returns the coordinates of the front of the kart. This is used for
+     *  determining when the lap line is crossed. */
+    virtual const Vec3& getFrontXYZ() const { return m_xyz_front; }
+    // ------------------------------------------------------------------------
     /** Returns the initial position of this kart. */
     virtual int    getInitialPosition  () const { return m_initial_position; }
     // ------------------------------------------------------------------------

src/modes/linear_world.cpp

@@ -174,7 +174,7 @@ void LinearWorld::update(float dt)
         // rescued or eliminated
         if(kart->getKartAnimation()) continue;
 
-        kart_info.getTrackSector()->update(kart->getXYZ());
+        kart_info.getTrackSector()->update(kart->getFrontXYZ());
         kart_info.m_overall_distance = kart_info.m_race_lap
                                      * m_track->getTrackLength()
                         + getDistanceDownTrackForKart(kart->getWorldKartId());

src/tracks/check_structure.cpp

@@ -100,7 +100,7 @@ void CheckStructure::update(float dt)
     World *world = World::getWorld();
     for(unsigned int i=0; i<world->getNumKarts(); i++)
     {
-        const Vec3 &xyz = world->getKart(i)->getXYZ();
+        const Vec3 &xyz = world->getKart(i)->getFrontXYZ();
         if(world->getKart(i)->getKartAnimation()) continue;
         // Only check active checklines.
         if(m_is_active[i] && isTriggered(m_previous_position[i], xyz, i))